Therapeutic usage of the non-steroidal anti-inflammatory drugs

A quantitative evaluation of the regulatory assessment of the benefits and risks of rofecoxib relative to naproxen: an application of the incremental net-benefit framework

PURPOSE

To undertake a quantitative benefit-risk analysis of rofecoxib relative to naproxen using an incremental net-benefit (INB) analysis from the societal perspective, using the same data evaluated by the Health Canada and US FDA expert advisory panels.

METHODS

We developed a discrete event simulation model to calculate the INB of rofecoxib relative to naproxen in arthritis patients over a 1-year time horizon. All outcomes were weighted using societal utilities for each health state which facilitated the use of quality-adjusted life years (QALYs) as the outcome. Probability distributions were incorporated for each model parameter to facilitate a probabilistic analysis using second-order Monte Carlo simulation.

RESULTS

In the base case analysis, the mean INB (SD) of rofecoxib relative to naproxen was 0.0002 (0.415) QALYs per patient over 12 months of treatment, or 0.2 QALYs per 1000 patients treated. The probabilistic sensitivity analysis resulted in a mean INB of 0.0022 QALYs (95%CI -0.0005, 0.0051). Overall, the INB associated with rofecoxib relative to naproxen was ≥0 in 94% of the iterations of the model.

CONCLUSIONS

This analysis illustrates the application of the incremental net-benefit framework to quantitative benefit-risk evaluation, and suggests that the potential benefits of rofecoxib outweigh the potential harms relative to naproxen over 1 year from the societal perspective under the assumptions of this model.

A randomized controlled trial of piroxicam in the management of acute ankle sprain in Australian Regular Army recruits. The Kapooka Ankle Sprain Study

Three hundred sixty-four Australian Regular Army recruits with acute ankle sprains sustained during training were randomized to treatment with either piroxicam or placebo. Compared with the placebo group, subjects treated with piroxicam had less pain, were able to resume training more rapidly, were treated at lower cost, and were found to have increased exercise endurance on resumption of activity. Nausea was the only side effect reported significantly more often in the treatment group than in the placebo group (6.8% versus 0.3%). Interestingly, subjects treated with piroxicam showed some evidence of local abnormalities such as instability and reduced range of movement. We conclude that nonsteroidal antiinflammatory agents should form an integral part of the treatment of acute ankle sprains.

Efficacy of non-steroidal anti-inflammatory drugs for low back pain: a systematic review of randomised clinical trials

PURPOSE

To assess the efficacy of non-steroidal anti-inflammatory drugs (NSAIDs) for low back pain.

DATA SOURCES

Computer aided search of published randomised clinical trials and assessment of the methods of the studies.

STUDY SELECTION

26 randomised clinical trials evaluating NSAIDs for low back pain were identified.

DATA EXTRACTION

Score for quality (maximum = 100 points) of the methods based on four categories: study population; interventions; effect measurement; data presentation and analysis. Determination of success rate per study group and evaluation of different contrasts. Statistical pooling of placebo controlled trials in similar patient groups and using similar outcome measures.

RESULTS

The methods scores of the trials ranged from 27 to 83 points. NSAIDs were compared with placebo treatment in 10 studies. The pooled odds ratio in four trials comparing NSAIDs with placebo after one week was 0.53 (95% confidence intervals 0.32 to 0.89) using the fixed effect model, indicating a significant effect in favour of NSAIDs compared with placebo. In nine studies NSAIDs were compared with other (drug) therapies. Of these, only two studies reported better results of NSAIDs compared with paracetamol with and without dextropropoxyphene. In the other trials NSAIDs were not better than the reference treatment. In 11 studies different NSAIDs were compared, of which seven studies reported no differences in effect.

CONCLUSIONS

There are flaws in the design of most studies. The pooled odds ratio must be interpreted with caution because the trials at issue, including the high quality trials, did not use identical outcome measures. The results of the 26 randomised trials that have been carried out to date, suggest that NSAIDs might be effective for short-term symptomatic relief in patients with uncomplicated low back pain, but are less effective or ineffective in patients with low back pain with sciatica and patients with sciatica with nerve root symptoms.

Comparative in vitro and in vivo bioavailability of naproxen from tablet and caplet formulations

A 500 mg dose of naproxen in a caplet formulation (product A) or a tablet (Naprosyn 500, product B) was administered to 14 fasting healthy subjects on two separate occasions, separated by a 1-2 week washout period in an open, randomized crossover. Blood samples were drawn periodically and plasma naproxen concentrations measured by HPLC. The median time Tmax to reach peak concentration for product A was shorter than that for product B (1.025 h versus 1.5 h) but A and B were similar with respect to median peak plasma concentration Cmax (77.9 mg l-1 versus 71.4 mg l-1), and average area AUC0-infinity under the plasma concentration-time curve (1210.2 mg l-1 h versus 1211.0 mg l-1 h). In vitro parameters (A versus B) of mean dissolution time MDT (5.03 min versus 15.0 min), and time for 70% dissolution T70 (6.67 min versus 20.2 min), differed significantly.

Description of a mechanistic approach to pain management in advanced cancer. Preliminary report

A mechanistic approach to advanced cancer pain management is proposed, based on the clinically perceived anatomical and pathophysiological mechanisms of pain generation. It is an extension of the World Health Organisation (WHO) analgesic ladder in which severity of pain is the principal determinant of analgesic choice. The mechanistic categories are: superficial somatic, deep somatic, visceral and neurogenic (mixed or pure, i.e., nociceptive component present or absent). Allocation of pain to the different categories is based on clinical history, physical findings and investigations to establish the site and extent of active primary or metastatic tumor deposits, and evidence of previous response to medication. Drug choice sequence is determined by the dominant pain mechanism judged to be present and not the severity of the pain. In order to describe this approach, mechanisms of pain, disease distribution and drug treatment have been analysed in the first 20 consecutive patients who consented to enter a longitudinal pain description and evaluation study on admission to an inpatient hospice unit. Despite a high exclusion rate from research standard monitoring due to severity of illness and related factors, the majority of eligible patients approached to enter the study did so, and the pain scoring was well tolerated. The implications of this for future research and clinical practice are discussed. In 6 patients only 1 pain mechanism was identified (visceral 4, deep somatic 2). Two mechanisms were present in 8 patients and 3 mechanisms in 6 patients. The deep somatic mechanism was identified in 15 patients, visceral mechanism in 13, neurogenic in 10 and superficial somatic in 2.(ABSTRACT TRUNCATED AT 250 WORDS)

A double blind, multicentre, placebo controlled trial of lornoxicam in patients with osteoarthritis of the hip and knee

Lornoxicam is a new non-steroidal anti-inflammatory agent (NSAID) with a similar pharmacological profile to other oxicams and a potency 10 times greater than piroxicam. A multicentre, randomised, double blind, parallel group study was undertaken to compare the efficacy and tolerance of four weeks' treatment with lornoxicam (6 mg once daily, 4 mg twice daily, and 6 mg twice daily) and placebo in patients with osteoarthritis of the hip or knee. A dose related efficacy of lornoxicam was shown by the numbers of patients in each treatment group who withdrew from the trial owing to inadequate symptom relief (12/40 (30%) receiving placebo, 6/40 (15) receiving lornoxicam 6 mg daily, 4/40 (10%) receiving lornoxicam 8 mg daily, and none receiving lornoxicam 12 mg daily). This effect was confirmed by pain relief scores, which were significantly better than placebo during treatment with lornoxicam 8 mg and 12 mg daily, the effect of 12 mg daily being significantly superior to that of 8 mg daily. Similar results were obtained from functional status scores. Mean functional index (Lequesne) scores were significantly greater than placebo only at a daily dose of 12 mg lornoxicam. Lornoxicam was generally well tolerated, though some gastrointestinal side effects were seen as has been reported with other NSAIDs. Laboratory investigations showed no evidence of drug toxicity.

The problems and pitfalls of NSAID therapy in the elderly (Part II)

The elderly are most susceptible to pharmacokinetic drug interactions between various NSAIDs and anticoagulants, sulphonylurea hypoglycaemic agents, certain anticonvulsants, methotrexate, digoxin, aminoglycosides and lithium. Pharmacodynamic interactions between some NSAIDs and antihypertensive drugs, anticoagulants, sulphonylurea agents and other NSAIDs are also potentially significant in the elderly. Despite the finding that mean therapeutic responses of large groups of patients have been generally equivalent for the wide range of NSAIDs studied thus far, it is also apparent that marked variability exists in the response of individual patients to different NSAIDs. Subsequent dosage increments may predispose 'nonresponders' and some less sensitive 'responders' to toxicity from NSAIDs. This interindividual variability in response to NSAIDs may be contributed to by the differing physicochemical properties of NSAIDs, physician prescribing habits and patient expectations, variations in NSAID pharmacokinetics, and the differing effects of NSAIDs other than their common ability to inhibit prostaglandin synthesis. The principles for drug prescribing in the elderly are no different from those that should be applied to the prescribing of medication in any patient. The clinician should strive to make a diagnosis and should avoid treating symptoms in isolation. Critical assessment of the indication for prescribing NSAID therapy must include consideration of the available effective and safe alternatives. If an NSAID is commenced the lowest effective dose should be the desired goal, but after an appropriate trial it is acceptable clinical practice to employ an alternative NSAID. There is no justification for combination NSAID therapy. The progress of each patient must be carefully monitored, particularly during the first few months of treatment, while periodic review of the ongoing need for the NSAID is essential.